A supercritical fluid dyeing process and apparatus

Abstract

This invention discloses a supercritical fluid dyeing method. A supercritical fluid is introduced into a dye storage tank containing dye. After the temperature and pressure in the dye storage tank reach set values, the supercritical fluid containing dissolved dye is introduced into a dyeing vessel containing the material to be dyed. The supercritical fluid containing dissolved dye is circulated between the dyeing vessel and the dye storage tank. After a preset period, the dyeing of the material is completed. The supercritical fluid is a mixture of carbon dioxide and nitrogen. This method can improve the problems of poor fiber color brightness and low dyeing depth.

Description

Technical Field

[0001] This invention relates to the field of fiber dyeing technology, and more specifically to a supercritical mixed fluid dyeing method and apparatus. Background Technology

[0002] The dyeing and printing industry has always been a typical heavily polluting and energy-intensive industry. According to statistics from the China Dyeing and Printing Industry Association, there are over 1,700 large-scale dyeing and printing enterprises nationwide, with an annual wastewater discharge of up to 2 billion tons, accounting for 11% of the country's total wastewater discharge. As a major water polluter, its wastewater discharge and total pollutant volume rank second and fourth respectively among all industrial sectors in China. The nearly 10% of untreated dyes and chemicals left behind result in wastewater that is diverse, highly alkaline, concentrated, and toxic, making it difficult to treat industrially. In recent years, research on supercritical fluid dyeing technology has gradually attracted attention. Supercritical fluid dyeing technology utilizes the strong swelling effect of a fluid on fibers and its good solubility for certain dyes in a supercritical state, allowing dyes to be rapidly applied to fibers in an anhydrous state, thus achieving fiber dyeing. It is a new type of environmentally friendly anhydrous dyeing technology. However, existing supercritical mixed fluid dyeing methods still suffer from poor fiber color vibrancy and low dyeing depth. Summary of the Invention

[0003] The purpose of this invention is to overcome the above-mentioned defects or problems in the prior art and to provide a supercritical mixed fluid dyeing method and apparatus, which can improve the problems of poor fiber color brightness and low dyeing depth.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A supercritical mixed fluid dyeing method involves introducing a supercritical mixed fluid into a dye storage tank containing dye. After the temperature and pressure in the dye storage tank reach a set value, the supercritical mixed fluid containing dissolved dye is introduced into a dyeing kettle containing the object to be dyed. The supercritical mixed fluid containing dissolved dye is then circulated between the dyeing kettle and the dye storage tank. After a preset period, the dyeing of the object to be dyed is completed. The supercritical mixed fluid is a supercritical fluid composed of carbon dioxide and nitrogen.

[0006] Furthermore, in the supercritical fluid, carbon dioxide accounts for 75%-95% by volume.

[0007] Furthermore, in the phrase "after the temperature and pressure in the dye storage tank reach the set values", the set value of the temperature ranges from 90 to 140°C, and the set value of the pressure ranges from 18 to 30 MPa.

[0008] Furthermore, the preset period is 40-150 minutes.

[0009] Furthermore, the material to be dyed is fiber, yarn, or fabric wound around a dyeing warp beam. The dyeing warp beam is provided with a hollow channel and an air hole connecting the hollow channel and its outer wall. The supercritical mixed fluid containing the dye passes through the hollow channel and is sprayed out through the air hole to dye the material to be dyed wound around the dyeing warp beam.

[0010] Furthermore, the winding density of the material to be dyed on the dyeing warp beam is 0.2-0.5 kg / dm3, and its material is one or more of polyester, nylon, spandex, TPU, and TPEE, and its yarn structure is one or more of monofilament, multifilament, core-sheath structure yarn, core-spun yarn, and ply yarn.

[0011] Furthermore, the dye in the dye storage tank is one or more of disperse dyes, cationic dyes, or acid dyes.

[0012] Furthermore, the dyeing vessel maintains constant temperature and pressure during the dyeing process.

[0013] Furthermore, the present invention also provides a supercritical fluid dyeing apparatus for implementing the supercritical mixed fluid dyeing method as described in any of the preceding claims, comprising: a fluid generation system for generating a supercritical mixed fluid; and a dyeing system comprising a dye storage tank, a dyeing vessel, and a circulation pump; the dye storage tank storing dye and used to receive the supercritical mixed fluid generated by the fluid generation system; the dyeing vessel for holding the material to be dyed, and connected to the dye storage tank via the circulation pump to form a loop, so that the supercritical mixed fluid containing dissolved dye circulates between the dyeing vessel and the dye storage tank.

[0014] Furthermore, the material to be dyed is fiber, yarn, or fabric wound around a dyeing warp beam. The dyeing warp beam is provided with a hollow channel and an air hole connecting the hollow channel and its outer wall. The supercritical mixed fluid containing the dye passes through the hollow channel and is sprayed out through the air hole to dye the material to be dyed wound around the dyeing warp beam.

[0015] As can be seen from the above description of the present invention, compared with the prior art, the present invention has the following beneficial effects:

[0016] The supercritical mixed fluid dyeing method provided by this invention uses a supercritical mixed fluid that is a mixture of carbon dioxide and nitrogen. During the dyeing process, it can play a certain role in removing oil from the surface of the object to be dyed. At the same time, the product dyed by the supercritical mixed fluid has a higher brightness and a deeper dyeing degree.

[0017] In the supercritical fluid dyeing device used, the material to be dyed needs to be wound around a dyeing warp for dyeing. The dyeing warp is equipped with hollow pipes and vents. The supercritical mixed fluid containing dissolved dye passes through the hollow pipes and is then sprayed outward through the vents, so that the material to be dyed can be dyed from the inside out, resulting in a better dyeing effect. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A schematic diagram of an embodiment of the supercritical fluid staining apparatus provided by the present invention;

[0020] Figure 2 for Figure 1 A schematic diagram of the dyeing shaft and air inlet pipe in a supercritical fluid dyeing device.

[0021] Explanation of key figure labels:

[0022] 1. Carbon dioxide cylinder; 2. Nitrogen cylinder; 3. Carbon dioxide flow meter; 4. Nitrogen flow meter; 5. Condenser; 6. Gas storage tank; 7. Booster pump; 8. Dye storage tank; 9. Circulation pump; 10. Dyeing kettle; 11. Thermometer; 12. Pressure gauge; 13. Separation kettle;

[0023] Dyeing warp 14, hollow tube 141; pores 142;

[0024] Intake pipe 15. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are preferred embodiments of the present invention and should not be considered as excluding other embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0026] Unless otherwise expressly defined, the use of terms such as "first," "second," or "third" in the claims, description, and accompanying drawings of this invention is for distinguishing different objects and not for describing a specific order.

[0027] Unless otherwise expressly defined, in the claims, description, and accompanying drawings of this invention, the use of directional terms such as "center," "lateral," "longitudinal," "horizontal," "vertical," "top," "bottom," "inner," "outer," "upper," "lower," "front," "rear," "left," "right," "clockwise," and "counterclockwise" to indicate orientation or positional relationships is based on the orientation and positional relationships shown in the accompanying drawings and is only for the convenience of describing the invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the specific scope of protection of this invention.

[0028] Unless otherwise expressly defined, the terms "fixed connection" or "fixed connection" used in the claims, description and drawings of this invention should be interpreted broadly to refer to any connection in which there is no displacement or relative rotation relationship between the two parties, including non-removable fixed connection, detachable fixed connection, integral connection and fixed connection by other means or components.

[0029] In the claims, description and accompanying drawings of this invention, the terms "comprising," "having," and variations thereof are used to mean "including but not limited to."

[0030] Example 1

[0031] This embodiment provides a supercritical fluid staining apparatus, referring to... Figure 1 It includes a fluid generation system and a staining system.

[0032] The fluid generation system generates a supercritical mixed fluid and includes a carbon dioxide cylinder 1, a nitrogen cylinder 2, a carbon dioxide flow meter 3, a nitrogen flow meter 4, a condenser 5, a gas storage tank 6, and a booster pump 7. The dyeing system includes a dye storage tank 8, a circulation pump 9, a dyeing vessel 10, a thermometer 11, a press, and a separation vessel 13. The dye storage tank 8 contains dye and is used to receive the supercritical mixed fluid generated by the fluid generation system. The dyeing vessel 10 is used to hold the material to be dyed and is connected to the dye storage tank 8 via the circulation pump 9 to form a loop, allowing the supercritical mixed fluid containing dissolved dye to circulate between the dyeing vessel 10 and the dye storage tank 8.

[0033] Specifically, carbon dioxide cylinder 1 and nitrogen cylinder 2 store carbon dioxide and nitrogen under high pressure, respectively. These are connected to carbon dioxide flow meter 3 and nitrogen flow meter 4, respectively. The outputs of both flow meters 3 and 4 are connected to condenser 5. Through the corresponding flow meters, a precise gas mixture with a specific volume ratio can be obtained in condenser 5. Condenser 5 is then connected to gas storage tank 6. After the mixed gas condenses into a liquid state in condenser 5, it enters gas storage tank 6 and is then pressurized by booster pump 7 to form a supercritical mixed fluid, which is then introduced into dye storage tank 8 of the dyeing system.

[0034] Dye storage tank 8 stores dye and is equipped with a heater that can raise the temperature inside the dye storage tank 8 to a set value. After a supercritical fluid mixture is introduced into the dye storage tank 8, the dye in the dye storage tank 8 will dissolve in the supercritical fluid mixture. Then, the supercritical fluid mixture containing dissolved dye can be introduced into the dyeing kettle 10 through a circulation pump 9. The temperature inside the dye storage tank 8 can be controlled by the heater, while the pressure inside the dye storage tank 8 can be controlled by the air pressure when the supercritical fluid mixture is introduced, that is, the pressure inside the dye storage tank 8 can be controlled by controlling the booster pump 7.

[0035] The dyeing vessel 10 has an inlet pipe 15 and two outlet pipes. The inlet pipe 15 is connected to the outlet of the dye storage tank 8 via a circulation pump 9. One outlet pipe is connected to one inlet of the dye storage tank 8 via a valve, and the other outlet pipe is connected to the separation vessel 13. When the supercritical mixed fluid containing dissolved dye circulates between the dyeing vessel 10 and the dye storage tank 8, the valve between the dye storage tank 8 and the booster pump 7 is closed, and the valve between the dyeing vessel 10 and the separation vessel 13 is also closed. At this time, the supercritical mixed fluid containing dissolved dye will not escape, and the air pressure in the dyeing vessel 10 and the dye storage tank 8 can be kept constant. The dyeing vessel 10 also has a built-in heater to ensure that the temperature inside the dyeing vessel 10 is constant, and that the temperature inside the dyeing vessel 10 is equal to the temperature inside the dye storage tank 8, so as to provide a constant temperature and pressure circulating dyeing environment for the supercritical mixed fluid containing dissolved dye.

[0036] Among them, the pipeline between the dyeing kettle 10 and the dye storage tank 8 is equipped with heating wires to ensure that the supercritical mixed fluid containing the dye can maintain the set temperature during transportation.

[0037] The dyeing vessel 10 is equipped with a thermometer 11 and a pressure machine to measure the temperature and pressure in the dyeing vessel 10 in real time.

[0038] Reference Figure 2A dyeing warp beam 14 is installed inside the dyeing vessel 10. The dyeing warp beam 14 has a hollow pipe 141 and an air hole 142 connecting the hollow pipe 141 and its outer wall. One end of the hollow pipe 141 of the dyeing warp beam 14 is open and connected to one end of the air inlet pipe 15 of the dyeing vessel 10. The supercritical mixed fluid containing dissolved dye can enter the hollow pipe 141 of the dyeing warp beam 14 through the air inlet pipe 15 and then be discharged through the air hole 142. The dyeing warp beam 14 is used to wind the material to be dyed, which is fiber, yarn, or fabric wound on the dyeing warp beam 14. The supercritical mixed fluid containing dissolved dye can be sprayed out through the hollow pipe 141 and the air hole 142 to dye the material from the inside out, resulting in a better dyeing effect. Furthermore, the smooth flow path of the fluid facilitates the circulation of the fluid between the dyeing vessel 10 and the dye storage tank 8.

[0039] Example 2

[0040] This embodiment provides a supercritical mixed fluid staining method, which can be implemented using the supercritical fluid staining apparatus in Embodiment 1 above, and may include the following steps:

[0041] A supercritical mixed fluid is introduced into a dye storage tank 8 containing dye. After the temperature and pressure in the dye storage tank 8 reach a set value, the supercritical mixed fluid containing dissolved dye is introduced into a dyeing kettle 10 containing the material to be dyed. The supercritical mixed fluid containing dissolved dye is circulated between the dyeing kettle 10 and the dye storage tank 8. After a preset period, the dyeing of the material to be dyed is completed. The supercritical mixed fluid is a supercritical fluid composed of carbon dioxide and nitrogen.

[0042] Furthermore, it may specifically include the following steps:

[0043] S1. Wrap the material to be dyed around the dyeing warp 14 and place the dyeing warp 14 into the dyeing kettle 10, so that the air inlet pipe 15 of the dyeing kettle 10 is connected to the dyeing warp 14.

[0044] S2. Add the dye to the dye storage tank 8;

[0045] S3. Close the dyeing system and expel the air from the dyeing kettle 10;

[0046] S4. The gases from carbon dioxide cylinder 1 and nitrogen cylinder 2 are introduced into condenser 5 by adjusting the mixing ratio through carbon dioxide flow meter 3 and nitrogen flow meter 4, respectively.

[0047] S5. The mixed gas is condensed into a liquid state by condenser 5;

[0048] S6. The mixed gas is introduced into the dye storage tank 8 in a supercritical fluid state through the booster pump 7.

[0049] S7. After adjusting the temperature and pressure of the dye storage tank 8 and the dyeing kettle 10 to the set values, the circulation pump 9 starts working, and the supercritical mixed fluid containing dissolved dye circulates between the dyeing kettle 10 and the dye storage tank 8.

[0050] S8. After the preset period, the dyeing of the material to be dyed is completed;

[0051] S9. The supercritical mixed fluid containing the dye is introduced into the separation vessel 13. After separation, the mixed gas is discharged and the dye is recovered.

[0052] In the supercritical mixed fluid, carbon dioxide accounts for 75%-95% by volume. The phrase "after the temperature and pressure in the dye storage tank 8 reach the set values" refers to a temperature set value ranging from 90-140℃ and a pressure set value ranging from 18-30MPa. The preset period is 40-150 minutes. The material to be dyed is fiber, yarn, or fabric wound on a dyeing warp beam 14. The dyeing warp beam 14 is provided with a hollow pipe 141 and vents 142 connecting the hollow pipe 141 and its outer wall. The supercritical mixed fluid containing dissolved dye passes through the hollow pipe 141 and is sprayed out through the vents 142 to dye the material to be dyed wound on the dyeing warp beam 14. The winding density of the material to be dyed on the dyeing warp beam 14 is 0.2-0.5 kg / dm³. The dye in the dye storage tank 8 is one or more of disperse dyes, cationic dyes, or acid dyes. The dyeing kettle 10 maintains constant temperature and pressure during the dyeing process.

[0053] Specifically, in this embodiment, the winding density of the material to be dyed on the dyeing warp 14 is 0.3 kg / dm. 3 The dye used is 0.5% (owf) Disperse Red 167; the temperature setting is 120℃; the pressure setting is 23MPa; nitrogen and carbon dioxide account for 10% and 90% respectively; the preset dyeing period is 60 minutes. The material to be dyed can be fiber, yarn, or fabric, and its material can be one or more of polyester, nylon, spandex, TPU, and TPEE. The yarn structure can be one or more of monofilament, multifilament, core-sheath structure yarn, core-spun yarn, and ply yarn.

[0054] Example 3

[0055] Example 3 is based on Example 2, except that in this example, the winding density of the material to be dyed on the dyeing warp beam 14 is 0.3 kg / dm. 3 The dye used was 0.5% (owf) Disperse Red 167; the temperature setting was 120℃; the pressure setting was 23MPa; nitrogen and carbon dioxide accounted for 20% and 80% respectively; the preset dyeing period was 60min.

[0056] Example 4

[0057] Example 4 is based on Example 2, except that in this example, the winding density of the material to be dyed on the dyeing warp beam 14 is 0.2 kg / dm. 3 The dye used was 2.5% (owf) Disperse Black WSG300; the temperature setting was 120℃; the pressure setting was 26MPa; nitrogen and carbon dioxide accounted for 10% and 90% respectively; the preset dyeing period was 90min.

[0058] In addition, the present invention specification provides the following comparative examples.

[0059] Comparative Example 1

[0060] Comparative Example 1 is based on Example 2, except that the supercritical mixed fluid was adjusted to include only carbon dioxide, while the other steps and parameters were the same.

[0061] Comparative Example 2

[0062] Comparative Example 2 is based on Example 2, except that the material to be dyed is wound around a solid dyeing warp 14, and the supercritical mixed fluid containing the dye can only dye the material from the outside. The other steps and parameters are the same.

[0063] Comparative Example 3

[0064] Comparative Example 3 is based on Example 4, except that the supercritical mixed fluid was adjusted to include only carbon dioxide, while the other steps and parameters were the same.

[0065] The tests conducted on Examples 2, 3, and 4 and Comparative Examples 1, 2, and 3 were as follows:

[0066]

[0067] Regarding color depth (DL): a positive DL indicates that the test sample is lighter than the standard sample; a negative DL indicates that the test sample is darker than the standard sample. Regarding vividness (DC): a positive DC indicates that the test sample is more vivid than the standard sample; a positive DC indicates that the test sample is darker than the standard sample.

[0068] The test results above show that the supercritical mixed fluid dyeing method provided by this invention significantly improves the color depth and brightness of the dyed products.

[0069] The foregoing description of the specifications and embodiments is intended to explain the scope of protection of this invention, but does not constitute a limitation on the scope of protection of this invention. Modifications, equivalent substitutions, or other improvements to the embodiments of this invention or a portion thereof that can be obtained by those skilled in the art through logical analysis, reasoning, or limited experimentation, based on the teachings of this invention or the foregoing embodiments, in conjunction with common knowledge, general technical knowledge, and / or existing technology, should all be included within the scope of protection of this invention.

Claims

1. A supercritical mixed fluid staining method, characterized in that, Supercritical mixed fluid is introduced into the dye storage tank (8) containing dye. After the temperature and pressure in the dye storage tank (8) reach the set value, the supercritical mixed fluid containing dye is introduced into the dyeing kettle (10) containing the material to be dyed. The supercritical mixed fluid containing dye is circulated between the dyeing kettle (10) and the dye storage tank (8). After a preset period, the dyeing of the material to be dyed can be completed. The supercritical mixed fluid is a supercritical fluid composed of carbon dioxide and nitrogen; in the supercritical fluid, carbon dioxide accounts for 75%-95% by volume. In the phrase "after the temperature and pressure in the dye storage tank (8) reach the set value", the set value of the temperature is in the range of 90-140℃ and the set value of the pressure is in the range of 18-30MPa. The material to be dyed is fiber, yarn or fabric wound around a dyeing warp beam (14). The dyeing warp beam (14) is provided with a hollow pipe (141) and an air hole (142) connecting the hollow pipe (141) and its outer wall. A supercritical mixed fluid containing dye is sprayed out through the air hole (142) after passing through the hollow pipe (141) to dye the material to be dyed wound around the dyeing warp beam (14).

2. The supercritical mixed fluid staining method as described in claim 1, characterized in that, The preset period is 40-150 minutes.

3. The supercritical mixed fluid staining method as described in claim 1, characterized in that, The fabric to be dyed has a winding density of 0.2-0.5 kg / dm3 on the dyeing warp beam (14), and its material is one or more of polyester, nylon, spandex, TPU, and TPEE, and its yarn structure is one or more of monofilament, multifilament, core-sheath structure yarn, core-spun yarn, and ply yarn.

4. The supercritical mixed fluid staining method as described in claim 1, characterized in that, The dye in the dye storage tank (8) is one or more of disperse dyes, cationic dyes or acid dyes.

5. The supercritical mixed fluid staining method as described in claim 1, characterized in that, The dyeing vessel (10) maintains constant temperature and pressure during the dyeing process.

6. A supercritical fluid staining apparatus for implementing the supercritical mixed fluid staining method as described in any one of claims 1-5, characterized in that, include: A fluid generation system for generating supercritical mixed fluids; and The dyeing system includes a dye storage tank (8), a dyeing vessel (10), and a circulation pump (9); the dye storage tank (8) contains dye and is used to receive supercritical mixed fluid generated by the fluid generation system; the dyeing vessel (10) is used to place the material to be dyed, and it is connected to the dye storage tank (8) through the circulation pump (9) to form a loop, so that the supercritical mixed fluid containing dissolved dye circulates between the dyeing vessel (10) and the dye storage tank (8).

7. The supercritical fluid staining apparatus as described in claim 6, characterized in that, The material to be dyed is fiber, yarn or fabric wound around a dyeing warp beam (14). The dyeing warp beam (14) is provided with a hollow pipe (141) and an air hole (142) connecting the hollow pipe (141) and its outer wall. A supercritical mixed fluid containing dye is sprayed out through the air hole (142) after passing through the hollow pipe (141) to dye the material to be dyed wound around the dyeing warp beam (14).

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